Both are good units, the panisonic might be a little easier to read in the sun, the alpine will be easier to adjust volume in the boat with the knob. The panasonic will run your amp(s) a little bit cleaner. Go with the one that you think matches the looks/colors of the boat or which you prefer

Alpine for sure. Panasonic makes really nice CD players and are very good value, but you can't beat the durability of an Alpine. The Alpine uses a worm-gear drive in the transport and silicon filled dampers to combat skipping. Also, most new Alpines are Sirius or XM ready, have easy hook-ups to run auxiliary sources such as Ipod. It's the way to go for a boat for sure.

How much are you looking to spend? I just picked up a Panasonic CQ-C9800U on line for $329.00. It doesn't have the satilite radio option, but does do MP3 and has a aux input which was what I was looking for. I installed it yesterday, but don't have the amps or speakers done yet so I can't give you any sound feed back. I looks like it will be a nice deck. I like the physical looks as well.